16098-16-1Relevant articles and documents
Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium
Fiebor, Alphonse,Tia, Richard,Makhubela, Banothile C. E.,Kinfe, Henok H.
supporting information, p. 1859 - 1870 (2018/08/21)
Unlike their SCS analogues, SNS pincer complexes are poorly studied for their use in coupling reactions. Accordingly, a series of water soluble cationic Pd(II) SNS pincer complexes have been successfully synthesised and investigated in detail for their catalytic activity in Suzuki–Miyaura coupling reactions. By using only 0.5 mol % loading of the complexes, the coupling of inactivated aryl bromides and activated aryl chlorides with various boronic acids in water was achieved in excellent yields and the catalysts were found to be reusable for three cycles without a significant loss of activity. The investigation of the mechanism of the reaction revealed that a Pd(II) to Pd(IV) route is the more likely pathway which was further supported by computational studies.
Palladium incorporated on carbonaceous catalyst for Suzuki coupling reaction in water
Rathod, Pramod V.,Jadhav, Vrushali H.
supporting information, p. 1006 - 1009 (2017/02/18)
A new palladium incorporated carbonaceous catalyst Pd@CC[sbnd]SO3H[sbnd]NH2was synthesized by introducing palladium on glucose derived carbocatalyst. The catalyst was well characterized and was used for the Suzuki coupling of phenyl boronic acid with different aryl halides under aqueous conditions. This green methodology represents a ligand free, cost-effective and operationally convenient method for the synthesis of a variety of biaryl's under the conditions that are tolerant for a broad range of functional groups with good to excellent yields. Moreover, the catalyst could be easily recycled and reused at least five times without any significant loss of its catalytic activity.
A Highly Efficient Pd(PPh3)4-Catalyzed Suzuki Cross-Coupling Method for the Preparation of 2-Nitrobiphenyls from 1-Chloro-2-nitrobenzenes and Phenylboronic Acids
Elumalai, Vijayaragavan,Sandtorv, Alexander H.,Bj?rsvik, Hans-René
, p. 1344 - 1354 (2016/03/16)
A simple and efficient method for Suzuki cross-coupling of highly substituted and congested 1-chloro-2-nitrobenzene with phenylboronic acid was developed, investigated, and optimized. The reaction conditions comprises a mixture of MeOH and water (4:1) as the reaction medium, readily available and cheap Pd(PPh3)4 as catalyst, sodium carbonate as base, and microwave heating, which affords a fast reaction rate with good outcomes. The procedure was proven to have high functional group tolerance with phenylboronic acid and for 1-chloro-2-nitrobenzene and thus is a general method for the synthesis of 2-nitrobiphenyl. The target scaffold, 2-nitrobiphenyls, was produced in excellent yields with excellent selectivities in all cases. An efficient microwave-assisted and Pd(PPh3)4-catalyzed Suzuki cross-coupling method for the synthesis of 2-nitrobiphenyls from 1-chloro-2-nitrobenzenes and phenylboronic acids is disclosed. The method exhibits excellent selectivity and fast reaction rates, provides high to excellent yields, and tolerates both electron-withdrawing and -donating groups.
Silver-catalyzed arylation of (hetero)arenes by oxidative decarboxylation of aromatic carboxylic acids
Kan, Jian,Huang, Shijun,Lin, Jin,Zhang, Min,Su, Weiping
supporting information, p. 2199 - 2203 (2015/02/19)
A long-standing challenge in Minisci reactions is achieving the arylation of heteroarenes by oxidative decarboxylation of aromatic carboxylic acids. To address this challenge, the silver-catalyzed intermolecular Minisci reaction of aromatic carboxylic acids was developed. With an inexpensive silver salt as a catalyst, this new reaction enables a variety of aromatic carboxylic acids to undergo decarboxylative coupling with electron-deficient arenes or heteroarenes regardless of the position of the substituents on the aromatic carboxylic acid, thus eliminating the need for ortho-substituted aromatic carboxylic acids, which were a limitation of previously reported methods.
Transition-metal-free synthesis of phenanthridinones from biaryl-2-oxamic acid under radical conditions
Yuan, Ming,Chen, Li,Wang, Junwei,Chen, Shenjie,Wang, Kongchao,Xue, Yongbo,Yao, Guangmin,Luo, Zengwei,Zhang, Yonghui
supporting information, p. 346 - 349 (2015/02/19)
Na2S2O8-promoted decarboxylative cyclization of biaryl-2-oxamic acid for phenanthridinones has been developed. This work illustrates the first example of intramolecular decarboxylative amidation of unactivated arene under transition-metal-free conditions. Additionally, this approach provides an efficient and economical method to access biologically interesting phenanthridinones, an important structure motif in many natural products. (Chemical Equation Presented).
Synthesis, chemical reactivity, and photophysical properties of 2′,7′ phenylated rhodamine dyes
Natarajan, Arunkumar,Boden, Eugene P.,Burns, Andrew,McCloskey, Patrick J.,Rishel, Michael J.
, p. 4222 - 4226 (2014/07/22)
While exploring water soluble rhodamine based fluorescent polymeric systems for biological imaging applications we came across new rhodamine derivatives that possess interesting optical properties. We report the synthesis of three different 2′,7′-diphenylated rhodamine derivatives (1-3) with distinct photophysical properties. The three rhodamine derivatives differ by the number of methyl groups present on the nitrogens and their absorption maxima are red-shifted on increased methylation. We observed an unusual inertness of these compounds toward traditional DCC-DMAP esterification conditions, which we attribute to the ease of lactonization in the presence of even minute amounts of the nucleophile/base DMAP (pKa = 9.2). Synthesis of acrylate esters was successfully accomplished using MSNT (1-(Mesitylene-2-sulfonyl)-3-nitro-1,2, 4-triazole) coupling conditions using a much milder nucleophile/base, for example, N-methyl imidazole (pKa = 6.95).
Liquid triarylamines: The scope and limitations of piers-rubinsztajn conditions for obtaining triarylamine-siloxane hybrid materials
Kamino, Brett A.,Mills, Bridget,Reali, Christopher,Gretton, Michael J.,Brook, Michael A.,Bender, Timothy P.
experimental part, p. 1663 - 1674 (2012/04/17)
New liquid triarylamine-siloxane hybrid materials are produced using the Piers-Rubinsztajn reaction. Under mild conditions, liquid analogues of conventional and commonly crystalline triarylamines are easily synthesized from readily available or accessible intermediates. Using a diverse selection of triarylamines, we explored the effects of siloxane group and substitution pattern on the physical properties of these materials, and we have demonstrated that relatively large molecular liquids with desirable electrochemical properties can be produced. The interactions between the strongly Lewis acidic catalyst used for this transformation, tris(pentafluorophenyl)borane (BCF), and the Lewis basic triarylamine substrates were studied. Through UV-vis-NIR and 19F NMR spectroscopy, we have proposed that the catalyst undergoes a reversible redox reaction with the substrates to produce a charge transfer complex. The formation of this charge transfer complex is sensitive to the oxidation potential of the triarylamine and can greatly affect the kinetics of the Piers-Rubinsztajn reaction.
QUATERNARY AMMONIUM SALT COMPOUNDS
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Page/Page column 37, (2012/03/10)
[Problem] The object of the present invention is to provide a novel compound having 132 adrenergic receptor agonist activity and muscarinic receptor antagonist activity. [Means for Solving the Problem] The present invention is a quaternary ammonium salt compounds represented by formula (I), or a pharmaceutically acceptable salt thereof, with superior β32 adrenergic receptor agonist activity and muscarinic receptor antagonist activity.
Triphenylphosphine-mediated reductive cyclization of 2-nitrobiphenyls: A practical and convenient synthesis of carbazoles
Freeman, Adam W.,Urvoy, Marie,Criswell, Megan E.
, p. 5014 - 5019 (2007/10/03)
The synthesis of a series of substituted carbazoles from the corresponding 2-nitrobiphenyl derivatives using a novel modification of the Cadogan reaction is described. Cyclization of the 2-nitrobiphenyls was achieved via reductive deoxygenation of the nitro groups using a slight excess of triphenylphosphine in a suitable solvent. We have observed a temperature dependence on the extent of conversion under these conditions, with higher boiling solvents affording higher yields across a range of substrates. The new reaction conditions are very straightforward and convenient to execute, tolerate a broad range of functional groups, and yield carbazole products in the absence of unwanted side products.
Palladium catalysed Suzuki reactions of fluoroarenes
Widdowson, David A.,Wilhelm, Rene
, p. 578 - 579 (2007/10/03)
A novel palladium catalysed cleavage of C-F bonds in a series of Suzuki reactions of aryl fluorides is described together with a discussion of the mechanistic implications.
